Multi-node networking laser communication system

Abstract

The invention belongs to the field of laser communication, and particularly relates to a multi-node networking laser communication system, which realizes signal light capture in a wide field of view through an ultra-wide angle system, performs light field segmentation and imaging to a focal plane of a DMD (Digital Micromirror Device) by using a dodging system, and controls the on-off state of the DMD through a dynamic adjustment system. Therefore, the signal light in the target direction is spatially gated, and the link establishment is completed after the signal light is collimated by a relay system. The launching process is contrary. The multi-node networking laser communication system realizes a receiving and transmitting bidirectional function based on the same optical path, and has the advantages of multi-target rapid inertia-free tracking, simplified system structure, strong spatial filtering capability, low initial capturing precision and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of laser communication, and particularly relates to a multi-node networking laser communication system. BACKGROUND

[0002] With the rapid iteration of information technology, the industry demand for Internet of Everything continues to rise, and the requirements for communication capacity, communication distance and communication rate in various fields of society show exponential growth. High-digital, high-quality and high-identification information transmission equipment has also emerged in large numbers. Under this background, laser communication has become the core and key technology supporting the next generation of satellite Internet, intelligent constellation and space information infrastructure, with its ultra-high transmission rate of Gbps or even Tbps.

[0003] With the deep evolution of space missions towards data-intensive, communication-networked and platform-miniaturized directions, emerging application scenarios such as low-orbit constellation systems, deep space exploration missions and on-orbit intelligent services have put forward rigorous requirements for the performance and functions of laser communication systems. Such requirements not only reflect the leap in the order of magnitude of transmission rate and network capacity, but also put forward overall improvement appeals for multi-dimensional indicators such as link adaptive capability, multi-node cooperative communication capability and high-stability control capability of laser communication systems in complex dynamic environments. Therefore, laser communication systems must have core technical foundations such as inter-satellite link (ISL) dynamic networking, multi-terminal cooperative communication and high-stability link control.

[0004] Currently, traditional laser communication systems generally adopt a point-to-point communication architecture, and each communication node needs to be independently configured with a complete set of transceiver terminals. In the beam alignment and tracking link, traditional systems mostly rely on mechanical APT (acquisition, pointing and tracking) systems, which have inherent defects such as large inertia and slow scanning speed, making it difficult to adapt to high-dynamic and multi-user networking communication scenarios.

[0005] At the same time, the point-to-point architecture design also leads to a series of chain problems: first, the system complexity and hardware cost are high, and when the number of networking nodes increases, each node needs to be equipped with independent optical transmitting / receiving equipment, supporting control systems and auxiliary equipment, greatly increasing the hardware deployment cost and later maintenance difficulty; second, the overall energy consumption of the system continues to rise, and independent equipment configuration requires each node to provide continuous and stable power supply, which puts a heavy burden on the energy supply system. SUMMARY

[0006] Therefore, the present application aims to provide a multi-node networking laser communication system to solve the technical problems of node complexity, high energy consumption and high alignment accuracy of existing laser communication systems in multi-node networking.

[0007] To achieve the above object, the technical solution of the present invention is realized as follows: A multi-node networking laser communication system, comprising: An ultra-wide-angle system for achieving wide-field-of-view coverage within ±65°, which is used to receive the signal light emitted by the target within the wide field of view when acting as the receiving end, and to emit the signal light to the target within the wide field of view when acting as the transmitting end; The front focal point of the light homogenizing system coincides with the rear focal point of the ultra-wide-angle system. When acting as the receiving end, it is used to homogenize and spatially divide and image the received signal light. When acting as the transmitting end, it is used to combine and direct the emitted signal light; A spatial light modulation system is arranged on the focal plane of the light homogenizing system. When acting as the receiving end, it is used to perform spatial filtering and field-of-view gating on the homogenized and spatially divided and imaged signal light. When acting as the transmitting end, it is used to perform reflection direction gating on the emitted signal light; A relay system. The front focal plane of the relay system is provided with a spatial light modulation system, and the rear focal plane of the relay system is the exit pupil of the relay system. When acting as the receiving end, it is used to collimate the gated signal light. When acting as the transmitting end, it is used to relay the emitted signal light to the spatial light modulation system; A coupling system. When acting as the receiving end, it is used to couple the collimated signal light of the relay system to the communication terminal. When acting as the transmitting end, it is used to couple the signal light emitted by the communication terminal to the relay system.

[0008] Furthermore, the ultra-wide-angle system includes 6 lenses, namely: The first lens is a plano-concave lens, with an optical aperture D1 satisfying 76mm < D1 < 84mm and a focal power Φ1 satisfying -0.025 < Φ1 < -0.015; The second lens is a meniscus lens, with an optical aperture D2 satisfying 26mm < D2 < 34mm and a focal power Φ2 satisfying -0.02 < Φ2 < -0.015; The third lens is a meniscus lens, with an optical aperture D3 satisfying 20mm < D3 < 35mm and a focal power Φ3 satisfying -0.025 < Φ3 < -0.015; The fourth lens is a double convex lens, with an optical aperture D4 satisfying 25mm < D4 < 35mm and a focal power Φ4 satisfying 0.015 < Φ4 < 0.025; The fifth lens is a double convex lens, with an optical aperture D5 satisfying 30mm < D5 < 40mm and a focal power Φ5 satisfying 0.01 < Φ5 < 0.02; The sixth lens is a meniscus lens, with an optical aperture D6 satisfying 25mm < D6 < 35mm and a focal power Φ6 satisfying 0.01 < Φ6 < 0.02; The central interval d1 between the first lens and the second lens satisfies 65mm < d1 < 68mm; The central interval d2 between the second lens and the third lens is 40 mm < d2 < 42 mm; The central interval d3 between the third lens and the fourth lens is 6 mm < d3 < 8 mm; The central interval d4 between the fourth lens and the fifth lens is 15 mm < d4 < 17 mm; The central interval d5 between the fifth lens and the sixth lens is 10 mm < d5 < 12 mm.

[0009] Furthermore, the light homogenizing system includes a relay lens group and an imaging lens array; among which, The relay lens group includes 4 lenses, namely: The seventh lens, which is a meniscus lens, with an optical aperture D7 of 14 mm < D7 < 18 mm and a focal power Φ7 of 0.015 < Φ7 < 0.025; The eighth lens, which is a biconcave lens, with an optical aperture Ds of 14 mm < D8 < 18 mm and a focal power Φ8 of -0.05 < Φ8 < -0.04; The ninth lens, which is a meniscus lens, with an optical aperture D9 of 14 mm < D9 < 18 mm and a focal power Φ9 of 0 < Φ9 < 0.01; The tenth lens, which is a meniscus lens, with an optical aperture D10 of 16 mm < D10 < 20 mm and a focal power Φ10 of 0.01 < Φ10 < 0.02; The imaging lens array includes two lens groups arranged side by side. The optical parameters of the two lens groups are the same. Each lens group includes 2 lenses, namely: The eleventh lens, which is a meniscus lens, with an optical aperture D11 of 5 mm < D11 < 10 mm and a focal power Φ11 of 0.01 < Φ11 < 0.02; The twelfth lens, which is a biconvex lens, with an optical aperture D12 of 5 mm < D12 < 10 mm and a focal power Φ12 of 0.05 < Φ12 < 0.06; The central interval d6 between the seventh lens and the eighth lens is 10 mm < d6 < 12 mm; The central interval d7 between the eighth lens and the ninth lens is 8 mm < d7 < 10 mm; The central interval d8 between the ninth lens and the tenth lens is 7 mm < d8 < 9 mm; The central interval d9 between the tenth lens and the eleventh lens is 16 mm < d9 < 18 mm; The central interval d10 between the eleventh lens and the twelfth lens is 6 mm < d10 < 8 mm.

[0010] Furthermore, the spatial light modulation system includes Digital Micromirror Devices (DMD) and a dynamic adjustment system, which is used to adjust the switching states of the micromirror array of the DMD in real time.

[0011] Furthermore, the communication terminal includes a tracking system. The dynamic adjustment system drives the micromirrors at corresponding positions on the DMD to switch to the on state according to the feedback signal provided by the tracking system.

[0012] Furthermore, the relay system is an f-θ lens, which includes 4 lenses, namely: The thirteenth lens is a plano-convex lens, with an optical aperture D13 satisfying 15mm < D13 < 20mm and a focal power Φ13 satisfying 0.01 < Φ13 < 0.02; The fourteenth lens is a biconcave lens, with an optical aperture D14 satisfying 15mm < D14 < 20mm and a focal power Φ14 satisfying -0.02 < Φ14 < -0.01; The fifteenth lens is a biconvex lens, with an optical aperture D15 satisfying 15mm < D15 < 20mm and a focal power Φ15 satisfying 0.01 < Φ15 < 0.02; The sixteenth lens is a meniscus lens, with an optical aperture D16 satisfying 15mm < D16 < 20mm and a focal power Φ16 satisfying 0 < Φ16 < 0.01; The central interval d11 between the thirteenth lens and the fourteenth lens satisfies 1mm < d11 < 3mm; The central interval d12 between the fourteenth lens and the fifteenth lens satisfies 1mm < d12 < 3mm; The central interval d13 between the fifteenth lens and the sixteenth lens satisfies 1mm < d13 < 3mm.

[0013] Furthermore, the multi-node networking laser communication system further includes a TIR prism system located between the homogenizing system and the spatial light modulation system, which is used to deflect the signal light for homogenization and spatial segmentation imaging and the emitted signal light.

[0014] Furthermore, the TIR prism system includes a first TIR prism and a second TIR prism. The first TIR prism includes surface a, surface b, and surface c, and the second TIR prism includes surface d, surface e, and surface f. Surface b is the side surface of surface a and surface c, and surface c is glued to surface d. Total internal reflection of the signal light occurs on surface d, and the angle satisfies θr > arcsin1 / n, where θr is the angle between the optical axis of the signal light incident on surface d and the normal of surface d, and n is the refractive index of the second TIR prism.

[0015] Furthermore, the number of coupling systems is at least one.

[0016] Furthermore, there are two coupling systems. Each coupling system includes a plane mirror, a semi-transparent mirror, a first converging lens, and a second converging lens. The selected and collimated signal light is reflected by the plane mirror to the semi-transparent mirror. The semi-transparent mirror reflects a portion of the light to the first converging lens, which then converges and incident on a communication terminal. The semi-transparent mirror also transmits another portion of the light to the second converging lens, which then converges and incident on another communication terminal.

[0017] Compared with the prior art, the present invention can achieve the following beneficial effects: 1. This invention utilizes an ultra-wide-angle system to achieve a wide field of view coverage. Combined with the high-speed switching capability of DMD, it can quickly select and track multiple targets without any mechanical movement within the entire field of view, completely eliminating the time delay of mechanical scanning. The system response speed and reconfiguration capability are improved by orders of magnitude, perfectly adapting to highly dynamic, multi-node spatial networking scenarios.

[0018] 2. This invention utilizes the principle of optical path reversibility, enabling a multi-node networked laser communication system to function as both a receiver and a transmitter. This eliminates the need for multiple independent transceiver devices, significantly reducing the number of hardware devices and substantially lowering the system's size, weight, power consumption, and manufacturing costs, thus providing feasibility for large-scale constellation system deployment.

[0019] 3. This invention establishes a precise mapping between spatial angles and DMD pixel groups through a homogenizing system, and then uses the DMD for spatial gating. This not only allows multi-node networked laser communication systems to selectively establish links with targets in specific directions, but more importantly, it can directly eliminate background light and interference from non-target directions at the optical physics level, significantly improving the signal-to-noise ratio of the multi-node networked laser communication system. Simultaneously, the architecture of the multi-node networked laser communication system supports independent and parallel gating control of multiple discrete targets within a large field of view, laying the foundation for true simultaneous multi-target communication, thereby improving spectrum utilization and the overall communication capacity of the system.

[0020] 4. The ultra-wide-angle system of this invention achieves instantaneous global coverage with a large field of view through a special anti-long-range optical design, expanding the instantaneous search range of spatial signals. This design directly reduces the initial pointing accuracy requirements of multi-node networked laser communication systems, enabling multiple light signals in uncertain areas to be captured at once, eliminating the need for the slow scanning of traditional mechanical APT systems. This significantly reduces the time required for the first acquisition of light signals and improves the link establishment efficiency of multi-node networked laser communication systems in complex dynamic spatial environments.

[0021] 5. The front focal point of the homogenizing system precisely coincides with the rear focal point of the ultra-wide-angle system. Furthermore, the imaging lens array of the homogenizing system maps incident beams from different directions to different positions on the DMD focal plane, achieving beam homogenization and equal distribution. This design ensures the uniformity of all signal beams across the entire field of view and achieves spatial separation of each signal beam through beam partitioning, preventing signal aliasing. Combined with real-time feedback control from the dynamic adjustment system, it ensures the stability and reliability of the communication link, meeting the high data transmission quality requirements of space missions. Attached Figure Description

[0022] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A schematic diagram of the structure of the multi-node networked laser communication system described in the embodiment of the present invention; Figure 2 A schematic diagram of the structure of the ultra-wide-angle system described in the embodiment of the present invention; Figure 3 A schematic diagram of the light homogenizing system described in the embodiments of the present invention; Figure 4 A schematic diagram illustrating the field-of-view segmentation principle of the DMD as described in the embodiments of the present invention; Figure 5 This is a schematic diagram of the structure of the f-θ lens described in an embodiment of the present invention.

[0023] Explanation of reference numerals in the attached figures: Ultra-wide-angle system 1, First lens 11, Second lens 12, Third lens 13, Fourth lens 14, Fifth lens 15, Sixth lens 16, Beam homogenization system 2, Relay lens group 21, Seventh lens 211, Eighth lens 212, Ninth lens 213, Tenth lens 214, Imaging lens array 22, Eleventh lens 221, Twelfth lens 222, TIR prism system 3, First TIR prism 31, Second TIR prism 32, Spatial light modulation system 4, DMD 41, Dynamic adjustment system 42, Relay system 5, Thirteenth lens 51, Fourteenth lens 52, Fifteenth lens 53, Sixteenth lens 54, Coupling system 6, Plane mirror 61, Semi-transparent mirror 62, First converging lens 63, Second converging lens 64, Communication terminal 7. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0026] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0027] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "assembly," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] The following will refer to Figures 1-5 The invention will be described in detail with reference to the embodiments.

[0029] like Figure 1 As shown, the present invention provides a multi-node networked laser communication system that can function as both a receiver and a transmitter. When used as a receiver, it receives signal light emitted by a target; when used as a transmitter, it emits signal light towards the target.

[0030] The multi-node networked laser communication system includes an ultra-wide-angle system 1, a beam homogenizing system 2, a TIR prism system 3, a spatial light modulation system 4, a relay system 5, and a coupling system. The ultra-wide-angle system 1 provides wide-field coverage within a ±65° range. When acting as a receiver, it receives signal light emitted from targets within the wide-field; when acting as a transmitter, it emits signal light to targets within the wide-field. The front focal point of the beam homogenizing system 2 coincides with the rear focal point of the ultra-wide-angle system 1. When acting as a receiver, it homogenizes and spatially segments the received signal light; when acting as a transmitter, it combines and directionally guides the emitted signal light. The TIR prism system 3, when acting as a receiver, deflects the signal light used for homogenization and spatial segmentation imaging; when acting as a transmitter, it... The signal light to be transmitted is refracted at the receiving end; the spatial light modulation system 4 is set on the focal plane of the homogenizing system 2. When the spatial light modulation system 4 is the receiving end, it is used to perform spatial filtering and field-of-view gating on the homogenized and spatially segmented imaging signal light. When the spatial light modulation system 4 is the transmitting end, it is used to select the reflection direction of the transmitted signal light; the front focal plane of the relay system 5 is set with the spatial light modulation system 4, and the rear focal plane of the relay system 5 is the output plane of the relay system 5. When the relay system 5 is the receiving end, it is used to collimate the selected signal light. When the relay system 5 is the transmitting end, it is used to relay the transmitted signal light to the spatial light modulation system 4; when the coupling system 6 is the receiving end, it is used to couple the collimated signal light of the relay system 5 to the communication terminal 7. When the coupling system 6 is the transmitting end, it is used to couple the signal light transmitted by the communication terminal 7 to the relay system 5.

[0031] The following section uses a multi-node networked laser communication system as an example to explain the composition of each system in detail.

[0032] The ultra-wide-angle system, serving as the optical antenna in a multi-node networked laser communication system, plays a crucial role in achieving instantaneous global acquisition of signal beams across a wide field of view (±65°). Ultra-wide-angle system 1 is a telecentric image amplifier system, enabling superior beam transmission. Through a special anti-long-range optical design, ultra-wide-angle system 1 projects all potential signal beams within the large field of view into the homogenizing system 2 in parallel. For example... Figure 2As shown in the figure, the ultra-wide-angle system 1 includes six lenses, namely, the first lens 11, the second lens 12, the third lens 13, the fourth lens 14, the fifth lens 15, and the sixth lens 16 arranged in sequence. The first lens 11 is a plano-concave lens with an optical aperture D1 satisfying 76mm < D1 < 84mm and a focal power Φ1 satisfying -0.025 < Φ1 < -0.015; the second lens 12 is a meniscus lens with an optical aperture D2 satisfying 26mm < D2 < 34mm and a focal power Φ2 satisfying -0.02 < Φ2 < -0.015; the third lens 13 is a meniscus lens with an optical aperture D3 satisfying 20mm < D3 < 35mm and a focal power Φ3 satisfying -0.025 < Φ3 < -0.015; the fourth lens 14 is a biconvex lens with an optical aperture D4 satisfying 25mm < D4 < 35mm and a focal power Φ4 satisfying 0.015 < Φ4 < 0.025; the fifth lens 15 is a biconvex lens with an optical aperture D5 satisfying 30mm < D5 < 40mm and a focal power Φ5 satisfying 0.01 < Φ5 < 0.02; the sixth lens 16 is a meniscus lens with an optical aperture D6 satisfying 25mm < D6 < 35mm and a focal power Φ6 satisfying 0.01 < Φ6 < 0.02; the central interval d1 between the first lens 11 and the second lens 12 satisfies 65mm < d1 < 68mm; the central interval d2 between the second lens 12 and the third lens 13 satisfies 40mm < d2 < 42mm; the central interval d3 between the third lens 13 and the fourth lens 14 satisfies 6mm < d3 < 8mm; the central interval d4 between the fourth lens 14 and the fifth lens 15 satisfies 15mm < d4 < 17mm; the central interval d5 between the fifth lens 15 and the sixth lens 16 satisfies 10mm < d5 < 12mm.

[0033] The retrofocus design of the ultra-wide-angle system 1 uses the first lens 11, the second lens 12, and the third lens 13 with negative focal powers to compress the large field angle, and uses the fourth lens 14, the fifth lens 15, and the sixth lens 16 with positive focal powers to converge the light beam for imaging.

[0034] The light homogenization system 2 homogenizes the optical signals received by the ultra-wide-angle system 1, equally divides and splits the homogenized optical signals, and images them onto the focal plane of the DMD, providing panoramic light field information for subsequent digital signal processing and spatial domain filtering, thereby completely eliminating the time delay introduced by traditional mechanical scanning. As Figure 3 shown in the figure, the light homogenization system 2 includes a relay lens group 21 and an imaging lens array 22. The relay lens group 21 is an object-space telecentric system to承接 the light beam of the ultra-wide-angle system 1, and the imaging lens array 22 is an image-space telecentric system to实现视场共享.

[0035] The relay lens group 21 includes 4 lenses, namely the seventh lens 211, the eighth lens 212, the ninth lens 213 and the tenth lens 214. The seventh lens 211 is a meniscus lens, with an optical aperture D7 of 14mm < D7 < 18mm and a focal power Φ7 of 0.015 < Φ7 < 0.025; the eighth lens 212 is a biconcave lens, with an optical aperture D8 of 14mm < D8 < 18mm and a focal power Φ8 of -0.05 < Φ8 < -0.04; the ninth lens 213 is a meniscus lens, with an optical aperture D9 of 14mm < D9 < 18mm and a focal power Φ9 of 0 < Φ9 < 0.01; the tenth lens 214 is a meniscus lens, with an optical aperture D10 of 16mm < D10 < 20mm and a focal power Φ10 of 0.01 < Φ10 < 0.02; the central interval d6 between the seventh lens 211 and the eighth lens 212 is 10mm < d6 < 12mm; the central interval d7 between the eighth lens 212 and the ninth lens 213 is 8mm < d7 < 10mm; the central interval d8 between the ninth lens 213 and the tenth lens 214 is 7mm < d8 < 9mm.

[0036] The imaging lens array 22 includes two lens groups arranged side by side. The optical parameters of the two lens groups are the same. Each lens group includes 2 lenses, namely the eleventh lens 221 and the twelfth lens 222. The eleventh lens 221 is a meniscus lens, with an optical aperture D11 of 5mm < D11 < 10mm and a focal power Φ11 of 0.01 < Φ11 < 0.02; the twelfth lens 222 is a biconvex lens, with an optical aperture D12 of 5mm < D12 < 10mm and a focal power Φ12 of 0.05 < Φ12 < 0.06; the central interval d9 between the tenth lens 214 and the eleventh lens 221 is 16mm < d9 < 18mm; the central interval d10 between the eleventh lens 221 and the twelfth lens 222 is 6mm < d10 < 8mm.

[0037] As Figure 1As shown, the TIR prism system 3 includes a first TIR prism 31 and a second TIR prism 32. The first TIR prism 31 includes surface a, surface b, and surface c, where surface b is the side surface of surfaces a and c. Surface a serves as the incident surface of the first TIR prism 31, and surface c serves as the exit surface of the first TIR prism 31. The second TIR prism 32 includes surface d, surface e, and surface f. Surface c is bonded to surface d. Surface d serves as both the incident and reflecting surface of the second TIR prism 32, surface e serves as both the exit and incident surface of the second TIR prism 32, and surface f serves as the exit surface of the second TIR prism 32. The signal light emitted from the homogenizing system 2 enters the TIR prism system 3 through surface a, passes through surfaces c, d, and e in sequence, and then illuminates the working area of ​​DMD41. The selected signal light is reflected by DMD41, passes through surface e, and is incident on surface d. After total internal reflection on surface d, it exits from surface e and is incident on the relay system 5. The angle at which the beam is totally internally reflected on surface d satisfies θr > arcsin1 / n, where θr is the angle between the optical axis of the signal light incident on surface d and the normal to surface d, and n is the refractive index of the second TIR prism.

[0038] like Figure 1 As shown, the spatial light modulation system 4 includes a DMD41 and a dynamic adjustment system 42. The working area of ​​the DMD41 is divided into different sub-regions according to the beam partitioning of the homogenizing system 2. Each sub-region corresponds to the global field of view of the ultra-wide-angle system 1, and can modulate the signal light within the global field of view to achieve parallel sampling of the signal light. The dynamic adjustment system 42 is used to adjust the on / off state of the micromirror array of the DMD41 in real time. The signal light is imaged on the focal plane of the DMD41. By controlling the on / off state of the micromirror array through the dynamic adjustment system 42, a programmable spatial filter is formed, which adjusts only the micromirrors corresponding to the signal light in the target direction to the on state and reflects them to the subsequent relay system 5, thereby achieving background light suppression and target light selection in the spatial domain. The dynamic adjustment system 42 sends a pulse signal to the micromirror array. When the pulse signal is high, it controls the micromirrors to flip to a positive angle and be in an open state. The signal light is reflected to the relay system 5. When the pulse signal is low, it controls the micromirrors to flip to a negative angle and be in an off state. The signal light is deflected to the absorption area or a non-working path, thereby achieving spatial gating of the target beam and thus achieving field selection.

[0039] Ultra-wide-angle system 1 receives signals from spatial directions The light rays are collected and form corresponding light spots on the focal plane of the homogenizing system 2. The front focal point of the homogenizing system 2 precisely coincides with the rear focal point of the ultra-wide-angle system 1 to ensure that the incident light energy from different directions collected and converged by the homogenizing system 2 is received by the subsequent system without vignetting. The ultra-wide-angle system 1 converts the incident beam from a specific direction into a converging spherical wavefront and focuses it on the rear focal plane of the ultra-wide-angle system 1. The relay lens group 21 located at the front end of the homogenizing system 2 converts the incident beam into parallel light with an angle; in the imaging lens array 22 located at the rear end of the homogenizing system 2, each lens acts as an independent optical channel, receiving and processing only the local wavefront information corresponding to its sub-lens channel, and converging the beam to different positions on the focal plane of the homogenizing system 2 according to the incident angle. For a single beam incident, the energy of its focal spot is simultaneously collected by multiple lenses of the imaging lens array 22, and each lens forms a spot on the focal plane; for multiple incident beams at different angles, multiple separate spots are formed, and each lens simultaneously converges multiple spots corresponding to the incident angle on the focal plane.

[0040] The homogenizing system 2 can be considered as a spatial light field shaping element. In the imaging lens array 22 structure, each lens is equivalent to a sub-lens, and its function can be represented by a ray tracing model as follows: ; Where M represents the spatial mapping matrix of the uniform light system 2, which is used to describe the geometric transformation relationship from the incident light field to the image plane light field; The spatial coordinates of the light ray's position on the entrance plane when it enters the uniform light system 2; This represents the direction angle when the light enters the uniform light system 2, that is, the incident angle of the light in the x and y directions; This represents the spatial coordinates of the light ray on the focal plane after passing through the homogenizing system 2; This represents the exit direction angle of the light ray after passing through the homogenizing system 2, that is, the exit angle of the light ray in the x and y directions.

[0041] For an ideal imaging lens array 22: ; in, Let be the focal length of the lens. This matrix represents the following transformation relationship:

[0042] The above transformation relationship illustrates that the beams at each incident angle are mapped to different focal plane positions after the homogenizing system 2, thus achieving field-of-view sharing.

[0043] DMD41 is located on the focal plane of the homogenizing system 2. Incident beams from different incident directions are simultaneously imaged onto the focal plane of DMD41, achieving parallel sampling of spatial signals.

[0044] Each micromirror on the DMD41 has a center coordinate. When the size of the micromirrors is much smaller than the focal plane, they can be approximated as representing a tiny field-of-view unit on the focal plane. Therefore, the micromirror array of DMD41 is equivalent to pixelating the entire field of view of the ultra-wide-angle system 1. By controlling the algorithm to identify the position of the target spot and setting its corresponding micromirror pixel group to the on state, while setting the micromirrors in all other areas to the off state, only beams from the target direction are allowed to enter the subsequent optical path, thereby achieving extremely strong background light suppression and multi-target selection capabilities in space.

[0045] like Figure 4 As shown, the field-of-view segmentation principle of DMD41 is as follows: Figure 4 Images (a) and (b) show the on / off state of the micromirror, controlled by the dynamic adjustment system 42. Represented as: ; DMD's reflection function Defined as: ; Where d is the size of a single micromirror. This is a rectangular function.

[0046] The output field after passing through the ultra-wide-angle system 1, the light-diffusing system 2, and the DMD41 is: : .

[0047] That is, the beam is both spatially divided and shared by the homogenizing system 2, and selectively reflected by the DMD41.

[0048] The beam reflected by the micromirrors in the DMD41's on state is divergent, therefore a relay system 5 (the DMD is located at the front focal plane of the relay system 5, and the exit pupil of the relay system 5 is located at the rear focal plane of the relay system 5) is needed to receive and re-collimate the beam. The relay system 5 has two key functions: first, image transmission: relaying the modulation plane of the DMD41 to the system's exit pupil; second, beam collimation: converting the spherical wavefront from a specific pixel of the DMD41 into a plane wave, forming a collimated beam pointing in a specific direction. The direction of this emitted beam is uniquely determined by the coordinates of the activated micromirror cluster on the DMD41.

[0049] The relay system is an f-θ lens, which is an object-side telecentric system that converts the diverging beam reflected from the open micromirror of the DMD41 into a parallel beam. For example... Figure 5As shown, the f-θ lens includes four lenses, namely the thirteenth lens 51, the fourteenth lens 52, the fifteenth lens 53, and the sixteenth lens 54. The thirteenth lens 51 is a plano-convex lens with an optical aperture D13 satisfying 15mm < D13 < 20mm and a focal power Φ13 satisfying 0.01 < Φ13 < 0.02; the fourteenth lens 52 is a biconcave lens with an optical aperture D14 satisfying 15mm < D14 < 20mm and a focal power Φ14 satisfying -0.02 < Φ14 < -0.01; the fifteenth lens 53 is a biconvex lens with an optical aperture D15 satisfying 15mm < D15 < 20mm and a focal power Φ15 satisfying 0.01 < Φ15 < 0.02; the sixteenth lens 54 is a meniscus lens with an optical aperture D16 satisfying 15mm < D16 < 20mm and a focal power Φ16 satisfying 0 < Φ16 < 0.01; the central distance d11 between the thirteenth lens 51 and the fourteenth lens 52 satisfies 1mm < d11 < 3mm; the central distance d12 between the fourteenth lens 52 and the fifteenth lens 53 satisfies 1mm < d12 < 3mm; the central distance d13 between the fifteenth lens 53 and the sixteenth lens 54 satisfies 1mm < d13 < 3mm.

[0050] The number of coupling systems 6 is at least one. Figure 1 The case where the number of coupling systems 6 is two is shown. Each coupling system 6 includes a plane mirror 61, a semi-transmissive and semi-reflective mirror 62, a first converging lens 63, and a second converging lens 64. The selected and collimated signal light is reflected by the plane mirror 61 to the semi-transmissive and semi-reflective mirror 62. The semi-transmissive and semi-reflective mirror 62 reflects a part of the light to the first converging lens 63, and the light converges through the first converging lens 63 and is incident on one communication terminal 7. The semi-transmissive and semi-reflective mirror 62 also transmits another part of the light to the second converging lens 64, and the light converges through the second converging lens 64 and is incident on another communication terminal 7.

[0051] In an example of the present invention, the two communication terminals 7 are respectively a tracking system and a laser signal processing system. The dynamic adjustment system 42 drives the micromirrors at corresponding positions on the DMD 41 to switch to the on state according to the feedback signal provided by the tracking system. The laser signal processing system is used to modulate, demodulate, encode, and decode the signal light to achieve the conversion and transmission of information.

[0052] The above content details the working process and principle of the multi-node networking laser communication system as a transmitting end. According to the principle of optical path reversibility, when the multi-node networking laser communication system is used as a receiving end, it is just opposite to the transmitting end. The specific process is as follows: Signal input: The signal light is coupled into the coupling system 6 by the communication terminal 7 to form a collimated light beam.

[0053] Entering the relay system: The collimated light is incident from the rear focal plane (exit pupil plane) of the relay system 5.

[0054] DMD41 Selective Reflection: Due to the reversibility of the optical path, this collimated beam converges to a specific position on the front focal plane (i.e., DMD41) of the relay system 5. This position is determined by the incident angle of the collimated beam.

[0055] By dynamically adjusting the system 42, only the micromirror region on the DMD41 corresponding to the target emission direction is set to the on state, while all other micromirrors are in the off state. Therefore, the converging light will only be reflected by the micromirrors in the target region, while the light illuminating the off region will be guided away from the main optical path.

[0056] Entering Beam Homogenization System 2: The reflected light selected by DMD41 enters beam homogenization system 2. At this time, the function of beam homogenization system 2 changes from beam splitting imaging to beam combining and orientation.

[0057] Since the activated micromirrors on DMD41 are located within a specific sub-region, the reflected light will primarily enter the corresponding sub-lens channel in the imaging lens array 22. This sub-lens collimates the beam and projects it in a spatial direction uniquely corresponding to that sub-lens channel.

[0058] Ultra-wide-angle system 1 transmits: The beam, after being combined and oriented by the beam homogenizing system 2, is finally directed towards the distant target via the ultra-wide-angle system 1. The ultra-wide-angle system 1 acts as the transmitting antenna here, and due to its large field of view, it can effectively cover the area where the target may be located.

[0059] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0060] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A multi-node networked laser communication system, characterized in that, Comprising: An ultra-wide-angle system for achieving wide-field view coverage within ±65°, which is used to receive the signal light emitted by targets within the wide field of view when acting as a receiving end, and to emit signal light to targets within the wide field of view when acting as a transmitting end; The front focal point of the light homogenizing system coincides with the rear focal point of the ultra-wide-angle system. When acting as a receiving end, it is used to homogenize and spatially segment the received signal light for imaging. When acting as a transmitting end, it is used to combine and directionally guide the emitted signal light; A spatial light modulation system, which is arranged on the focal plane of the light homogenizing system. When acting as a receiving end, it is used to perform spatial filtering and field-of-view gating on the homogenized and spatially segmented imaged signal light. When acting as a transmitting end, it is used to perform reflection direction gating on the emitted signal light; A relay system. The front focal plane of the relay system is provided with the spatial light modulation system, and the rear focal plane of the relay system is the exit pupil of the relay system. When acting as a receiving end, it is used to collimate the gated signal light. When acting as a transmitting end, it is used to relay the emitted signal light to the spatial light modulation system; A coupling system, which is used to couple the collimated signal light of the relay system to the communication terminal when acting as a receiving end, and to couple the signal light emitted by the communication terminal to the relay system when acting as a transmitting end.

2. The multi-node networked laser communication system according to claim 1, characterized in that, The ultra-wide-angle system includes 6 lenses, namely: The first lens, which is a plano-concave lens, with an optical aperture D1 satisfying 76mm < D1 < 84mm and a focal power Φ1 satisfying -0.025 < Φ1 < -0.015; The second lens, which is a meniscus lens, with an optical aperture D2 satisfying 26mm < D2 < 34mm and a focal power Φ2 satisfying -0.02 < Φ2 < -0.015; The third lens, which is a meniscus lens, with an optical aperture D3 satisfying 20mm < D3 < 35mm and a focal power Φ3 satisfying -0.025 < Φ3 < -0.015; The fourth lens, which is a biconvex lens, with an optical aperture D4 satisfying 25mm < D4 < 35mm and a focal power Φ4 satisfying 0.015 < Φ4 < 0.025; The fifth lens, which is a biconvex lens, with an optical aperture D5 satisfying 30mm < D5 < 40mm and a focal power Φ5 satisfying 0.01 < Φ5 < 0.02; The sixth lens, which is a meniscus lens, with an optical aperture D6 satisfying 25mm < D6 < 35mm and a focal power Φ6 satisfying 0.01 < Φ6 < 0.02; The central interval d1 between the first lens and the second lens satisfies 65mm < d1 < 68mm; The central interval d2 between the second lens and the third lens satisfies 40mm < d2 < 42mm; The central interval d3 between the third lens and the fourth lens satisfies 6mm < d3 < 8mm; The central interval d4 between the fourth lens and the fifth lens satisfies 15mm < d4 < 17mm; The central interval d5 between the fifth lens and the sixth lens satisfies 10mm < d5 < 12mm.

3. The multi-node networked laser communication system according to claim 1, characterized in that, The light homogenizing system includes a relay lens group and an imaging lens array; among which, The relay lens group includes 4 lenses, namely: The seventh lens, which is a meniscus lens, with an optical aperture D7 satisfying 14mm < D7 < 18mm and a focal power Φ7 satisfying 0.015 < Φ7 < 0.025; The eighth lens is a biconcave lens with an optical aperture D8 satisfying 14mm < D8 < 18mm and a focal power Φ8 satisfying -0.05 < Φ8 < -0.04; The ninth lens is a meniscus lens with an optical aperture D9 satisfying 14mm < D9 < 18mm and a focal power Φ9 satisfying 0 < Φ9 < 0.01; The tenth lens is a meniscus lens with an optical aperture D10 satisfying 16mm < D10 < 20mm and a focal power Φ10 satisfying 0.01 < Φ10 < 0.02; The imaging lens array includes two lens groups arranged side by side. The two lens groups have the same optical parameters. Each lens group includes 2 lenses, namely: The eleventh lens is a meniscus lens with an optical aperture D11 satisfying 5mm < D11 < 10mm and a focal power ΦⱣ satisfying 0.01 < Φ11 < 0.02; The twelfth lens is a biconvex lens with an optical aperture D12 satisfying 5mm < D12 < 10mm and a focal power Φ12 satisfying 0.05 < Φ12 < 0.06; The central interval d6 between the seventh lens and the eighth lens satisfies 10mm < d6 < 12mm; The central interval d7 between the eighth lens and the ninth lens satisfies 8mm < d7 < 10mm; The central interval d8 between the ninth lens and the tenth lens satisfies 7mm < d8 < 9mm; The central interval d9 between the tenth lens and the eleventh lens satisfies 16mm < d9 < 18mm; The central interval d10 between the eleventh lens and the twelfth lens satisfies 6mm < d10 < 8mm.

4. The multi-node networked laser communication system according to claim 1, characterized in that, The spatial light modulation system includes a digital micromirror device and a dynamic adjustment system. The dynamic adjustment system is used to adjust the switching state of the micromirror array of the digital micromirror device in real time.

5. The multi-node networked laser communication system according to claim 4, characterized in that, The communication terminal includes a tracking system. The dynamic adjustment system drives the micromirrors at corresponding positions on the digital micromirror device to switch to the on state according to the feedback signal provided by the tracking system.

6. The multi-node networked laser communication system according to claim 1, characterized in that, The relay system is an f-θ lens and includes 4 lenses, namely: The thirteenth lens is a plano-convex lens with an optical aperture D13 satisfying 15mm < D13 < 20mm and a focal power Φ13 satisfying 0.01 < Φ13 < 0.02; The fourteenth lens is a biconcave lens with an optical aperture D14 satisfying 15mm < D14 < 20mm and a focal power Φ14 satisfying -0.02 < Φ14 < -0.01; The fifteenth lens is a biconvex lens with an optical aperture D15 satisfying 15mm < D15 < 20mm and a focal power Φ15 satisfying 0.01 < Φ15 < 0.02; The sixteenth lens is a meniscus lens with an optical aperture D16 satisfying 15mm < D16 < 20mm and a focal power Φ16 satisfying 0 < Φ16 < 0.01; The central interval d11 between the thirteenth lens and the fourteenth lens satisfies 1mm < d11 < 3mm; The central interval d12 between the fourteenth lens and the fifteenth lens satisfies 1mm < d12 < 3mm; The central interval d13 between the fifteenth lens and the sixteenth lens satisfies 1mm < d13 < 3mm.

7. The multi-node networked laser communication system according to claim 1, characterized in that, It also includes a TIR prism system located between the light homogenizing system and the spatial light modulation system, which is used to deflect the signal light for homogenization and spatial segmentation imaging and the emitted signal light.

8. The multi-node networked laser communication system according to claim 7, characterized in that, The TIR prism system includes a first TIR prism and a second TIR prism. The first TIR prism includes surfaces a, b, and c, and the second TIR prism includes surfaces d, e, and f. Surface b is a side surface of surfaces a and c. Surface c is cemented to surface d. The signal light undergoes total internal reflection at surface d, with the angle satisfying θr > arcsin1 / n, where θr is the angle between the optical axis of the signal light incident on surface d and the normal to surface d, and n is the refractive index of the second TIR prism.

9. The multi-node networked laser communication system according to claim 1, characterized in that, The number of coupled systems is at least one.

10. The multi-node networked laser communication system according to claim 9, characterized in that, There are two coupling systems. Each coupling system includes a plane mirror, a semi-transparent mirror, a first converging lens, and a second converging lens. The selected and collimated signal light is reflected by the plane mirror to the semi-transparent mirror. The semi-transparent mirror reflects a portion of the light to the first converging lens, which then converges and incident on a communication terminal. The semi-transparent mirror also transmits another portion of the light to the second converging lens, which then converges and incident on another communication terminal.

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